The present invention relates to a disk recording/reproduction apparatus for recording or reproducing data in or from a recording disk by using a movable recording/reproduction head and, more particularly, to a positioning mechanism of a recording/reproduction head.
A disk recording/reproduction apparatus, such as a magnetic, floppy, or optical disk apparatus, records or reproduces data on recording disks by using a movable recording/reproduction head.
The following two conventional positioning methods are employed in a disk recording/reproduction apparatus of this type in order to move a recording/reproduction head to an arbitrary position on a recording disk.
According to the first method, the rotation angle of a stepping motor used as a moving mechanism of a recording/reproduction head is set in one-to-one correspondence with a shift amount of the recording/reproduction head moved by the motor. A predetermined rotation angle is supplied to the motor in order to move the recording/reproduction head to an arbitrary position on a recording disk.
According to the second method, servo data as position data of each track of a recording disk is written in advance in either surface on the disk. Position data of a servo head which moves integrally with a recording/reproduction head is obtained in order to move the recording/reproduction head to an arbitrary position on the recording disk.
With the first method, however, although the recording/reproduction head can be positioned with a simple configuration, the rotation angle of the motor is related only to the shift amount of the recording/reproduction head, and not to a predetermined track of the recording disk. Assume that the head is located between two adjacent tracks before positional adjustment of the head. In this case, even when the recording/reproduction head is moved, it is located between two adjacent tracks, and not at a central portion of a track. Therefore, in order to obtain correspondence with a predetermined track, the head must be correctly adjusted and fixed at a track position on an adjustment disk in which track position data is correctly written. For example, a position adjustment pattern as shown in FIG. 1 is written in advance in an Nth track of the adjustment disk. An instruction is supplied from host computer 5 connected to floppy disk drive (FDD) 7 to read the Nth track, as shown in FIG. 2. FDD 7 moves recording/reproduction head 3 to the Nth track, reproduces the waveform recorded in the Nth track, and displays it (indicated by dotted line) on display unit 9. A person adjusting disk drive 7 observes the displayed waveform and positions head 3 so that head 3 is positioned at the correct central portion (indicated by a solid line) of the Nth track. However, such a position adjustment operation for the head moving mechanism is very complicated and thus cumbersome.
With the second method, in addition to the disk and the head for data recording/reproduction, a disk in which servo data is written, a head for reading out the servo data, a circuit for decoding the servo data, and so on are required, resulting in a complicated disk recording apparatus.